In the summer of 1739 Voltaire and his extraordinary and brilliant mistress, Emilie du Châtelet, made a brief sojourn in Brussels. While there Voltaire styled himself ‘the Ambassador of Utopia’ on his invitation cards, and found to his amusement that hardly anyone got the joke – they did not know what ‘Utopia’ meant or where it was. Yet in the light of Voltaire’s lifelong utopian quest for freedom – of thought, of conscience, of expression, of love, of the individual, of nations, of mankind at large – the title he adopted in jest surely applies in earnest.